Hundreds of customers were without power Tuesday as the demand for electricity surged at the start of what meteorologists say could be the longest, hottest heat wave so far this year.

There were reports of scattered power outages across New York City beginning Monday evening as customers cranked up their air conditioning, including in the Wakefield section of the Bronx and on the Upper West Side. Con Edison also warned of a 5-percent voltage reduction across Staten Island, though most people shouldn't notice the change.

The utility company has said it was prepared for possible power outages and has extra crews on call for the duration of the heat wave.

Temps surged into the 90s before noon in many parts of the tri-state Monday; in Central Park, the high reached 94 degrees. Heat advisories have been issued for most of the tri-state for the rest of the week.

Meteorologists say the heat index -- what it actually feels like outside -- is expected to be at or above 95 degrees.

The National Weather Service says the oppressive air could worsen by Thursday and Friday, when the heat index may reach 105 degrees in parts of the tri-state area.

Forecasters say the heat will feel the worst from 1 p.m. to 6 p.m. Officials say residents should be sure to stay hydrated, and anyone working outdoors during those times is advised to be in the shade as much as possible.

Isolated thunderstorms are possible for each day of the potential heat wave, though meteorologists say those showers will be extremely scattered and likely won't amount to much of a cooldown wherever they land. The intense heat is expected to break by next weekend as a cold front approaches.

New York City's Office of Emergency Management warned of heat illness, advising seniors and people with health conditions to stay in air conditioned areas. OEM says all New Yorkers should avoid strenuous activity and drink plenty of water.

The OEM says city cooling centers at senior centers, libraries and community centers will be open through Thursday.

During one heat wave stretching from late July to early August in 2006, about 40 people died from heat stroke in New York City, most of them in homes without air conditioning. Health officials later concluded that 100 more deaths during that time were related to the heat.
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